Reliable neighbor node discovery

ABSTRACT

Methods and systems for reliable neighbor discovery in wireless ad hoc networks are provided herein. In one aspect, embodiments of the present invention provide methods and systems for analyzing the quality of a communication link. In embodiments, several factors affecting link quality may be incorporated in the analysis, and basic and/or complex statistical and/or probabilistic analysis may be used. In another aspect, embodiments of the present invention provide methods and systems for neighbor node discovery that adapt to network and/or node operating conditions and that dynamically maintain a neighbor node set at a given node according to these conditions. In a further aspect, embodiments of the present invention extend the utility of neighbor node discovery beyond the customary role of data routing support into the problem of deploying an ad hoc network by providing a display module for displaying node connectivity information.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application of co-pending U.S. patentapplication Ser. No. 11/402,826, filed Apr. 13, 2006, titled “ReliableNeighbor Node Discovery,” now allowed, which is incorporated herein byreference in its entirety.

Statement under MPEP 310. The U.S. government has a paid-up license inthis invention and the right in limited circumstances to require thepatent owner to license others on reasonable terms as provided for bythe terms of Contract No. W15P7T-05-C-F600, awarded by the U.S. Army.

FIELD OF THE INVENTION

The present invention relates generally to wireless ad hoc networking.More particularly, the invention relates to methods and systems forreliable neighbor discovery in wireless ad hoc networks.

BACKGROUND OF THE INVENTION

Over the last decade, multihop routing for wireless ad hoc networks hasbeen the focus of numerous research efforts. With a multitude of routingprotocols having been proposed, a common challenge is faced in theability of the protocol to adapt to the expected but unpredictabletopological changes in wireless ad hoc networks.

In the literature, this is known as routing topology control and isdefined as the act of computing and maintaining a connected topologyamong network nodes, based on which data routing may be performed in thenetwork.

While topology control continues to receive considerable researchattention, an essential element at the basis thereof—neighbor nodediscovery—remains severely overlooked and is often simplisticallytreated in the design of routing protocols. Neighbor node discoveryrelates to the process by which a network node detects and dynamicallymaintains a neighbor node set, wherein the neighbor node set includesnetwork nodes with which direct symmetric communication links arepresent. By direct it is meant that there is no need to communicatethrough intermediate nodes.

Conventional methods for neighbor node discovery rely on a simplehello-reply exchange for detecting a neighbor node. However, while thisapproach may work in simulation, in practice, the success or failure ofa single exchange does not accurately describe the presence or absenceof a reliable communication link between two nodes.

What is needed therefore are methods and systems for reliable neighbornode discovery to support efficient data routing in wireless ad hocnetworks.

BRIEF SUMMARY OF THE INVENTION

Methods and systems for reliable neighbor discovery in wireless ad hocnetworks are provided herein.

In one aspect, embodiments of the present invention provide methods andsystems for analyzing the quality of a communication link using onlynetwork-level data transmission and reception. In embodiments, severalfactors affecting link quality may be incorporated in the analysis, andbasic and/or complex statistical and/or probabilistic analysis means maybe used.

In another aspect, embodiments of the present invention provide methodsand systems for neighbor node discovery that adapt to network and/ornode operating conditions and that dynamically maintain a neighbor nodeset at a given node according to these conditions.

In a further aspect, embodiments of the present invention extend theutility of neighbor node discovery beyond the customary role of datarouting support into the problem of deploying an ad hoc network byproviding a display module for displaying node connectivity information.

Further embodiments, features, and advantages of the present invention,as well as the structure and operation of the various embodiments of thepresent invention, are described in detail below with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

The accompanying drawings, which are incorporated herein and faun a partof the specification, illustrate the present invention and, togetherwith the description, further serve to explain the principles of theinvention and to enable a person skilled in the pertinent art to makeand use the invention.

FIG. 1 is an example illustration of a wireless ad hoc network.

FIG. 2 is an example illustration of the neighbor node discoveryproblem.

FIG. 3 is a process flowchart for reliable neighbor node discovery.

FIG. 4 is a block diagram of a system for reliable neighbor nodediscovery.

FIG. 5 is a block diagram of a wireless device having a neighbor nodediscovery module.

The present invention will be described with reference to theaccompanying drawings. The drawing in which an element first appears istypically indicated by the leftmost digit(s) in the correspondingreference number.

DETAILED DESCRIPTION OF THE INVENTION

Wireless Ad Hoc Networks

Wireless ad hoc networks consist of geographically distributed nodesthat communicate with one another over a wireless medium. Wireless adhoc networks date back to Packet Radio Networks (PRNs) and SurvivableRadio Networks (SRNs) developed by DARPA in the early 1970s and in the1980s.

Today, with the ever increasing popularity of mobile telephony andpersonal digital assistants, a number of potential commercialapplications of wireless ad hoc networks have been brought to theforefront. Examples of such applications include disaster relief,conferencing, home networking, sensor networking, personal areanetworking, and embedded computing applications.

Unlike wireless networks with infrastructure, such as cellular networksfor example, ad hoc networks have no fixed infrastructure. Accordingly,ad hoc network nodes are envisioned to self-configure into a network,whereby network control may be distributed among all the nodes in thenetwork.

Further in contrast to cellular networks, data communication in wirelessad hoc networks is peer-to-peer. In other words, data communication maytake place between any two nodes in an ad hoc network. However, giventhe lack of infrastructure and the characteristically limited nodecapabilities in an ad hoc network, data communication must generally beperformed in a multihop fashion.

Accordingly, a data packet in an ad hoc network may have to traversemultiple nodes in the network before reaching its intended destination.FIG. 1 is an example illustration of a wireless ad hoc network 100.Wireless ad hoc network 100 includes a plurality of nodes thatcommunicate wirelessly with each other. Nodes that are withincommunication (transmission and reception) range of each other are saidto be neighbor nodes, and may communicate using direct links with oneanother. Non-neighbor nodes employ intermediate nodes to communicateaccording to a multihop routing scheme. For example, as shown in FIG. 1,node A 102 communicates with non-neighbor node E 110 in 4 hops usingintermediate nodes B 104, C 106, and D 108. On the other hand, node A102 may communicate directly with node F 112 given that node F 112 iswithin communication range thereof. In practice, the ability to supportcommunication between two particular nodes is a complicated function ofthe nodes and their environment, depending not only on the inter-nodedistance but also the presence of obstructions in the intervening space,interference at either node, individual node characteristics (includingantenna gain, antenna orientation, and radio data rate), and othernearby nodes (through their use of the same radio bandwidth to carrynetwork traffic). Therefore, the ability to communicate can quicklyappear or disappear with changing conditions, especially when the nodesare mobile.

Neighbor Discovery in Wireless Ad Hoc Networks

As described above, reliable neighbor node discovery is essential foraccurate routing topology control in wireless ad hoc networks, andsubsequently for supporting efficient routing protocols for thesenetworks.

In the art, neighbor node discovery remains severely overlooked, and themajority of routing protocols for wireless ad hoc networks rely onsimple hello-reply exchange schemes for performing neighbor nodediscovery.

A drawback of these schemes is clearly that a simple hello-replyexchange is, in practice, not sufficient to accurately describe thecondition of a communication link. FIG. 2 is an example 200 thatillustrates the complexity of the neighbor node discovery problem.

Example 200 illustrates a wireless node A 202 having six adjacent nodesB 204, C 206, D 208, E 210, F 212, and G 214. For illustration purposesonly, the transmission range of node A 202 is shown as a uniform circlethat includes nodes B 204, C 206, D 208, E 210, F 212, and G 214. Inpractice, the transmission range of a wireless node is not a uniformcircle as shown in FIG. 2, for the reasons described above. Asingle-ended arrow from node A 202 to node B 204 denotes a one-waycommunication link from A 202 to B 204. A double-ended arrow betweennodes A 202 and C 206 denotes a two-way communication link between A 202and C 206. Accordingly, the link between A 202 and B 204 is said to beasymmetric. The link between A 202 and C 206 is a symmetric link.

A variety of factors determine whether a given communication link issymmetric or asymmetric. For the purpose of routing in the majority ofad hoc networking applications, neighbor node discovery entailsdiscovering nodes with which reliable symmetric communication links arepresent. By this it is meant that network traffic can be communicatedfrom a node to its neighbor with high probability of reception by theneighbor.

In example 200, nodes B 204, C 206, D 208, E 210, F 212, and G 214 areall theoretically within node A's transmission range. In practice,however, not all of nodes B 204, C 206, D 208, E 210, F 212, and G 214may be able to successfully receive data packets broadcast by node A 202with high probability. For example, receiver sensitivity at node F 212may preclude node F 212 from successfully receiving data packetsbroadcast from node A 202 which have low signal-to-noise SNR ratio. Onthe other hand, moving objects in the neighborhood of node E 210 ormobility of node E 210 may prevent reliable communication between nodesA 202 and E 210.

Accordingly, in example 200, the neighbor node set of node A 202includes nodes C 206, D 208, and G 214. However, due to volatility ofconditions in wireless ad hoc networks, the neighbor node set is not afixed set and will vary according to changes in network conditions,environmental conditions, and node mobility.

In addition to the above mentioned factors, which may be uncontrollableby a network designer, other controllable factors that affect linkquality exist, such as dynamic radio characteristics like packet size,data rate and transmission power.

For example, the data transmission rate used in communicating over alink may determine that link's error rate, and subsequently the qualityof the link. Further, a link's error rate may vary according to the sizeof packets being transmitted over that link. For example, smaller datapackets are generally less prone to bit errors and have a lowerprobability of colliding with other packets being broadcast in thenetwork than larger data packets.

Accordingly, link quality is a complex function of various factors, bothcontrollable and uncontrollable, and may not be accurately described bythe success or failure of a simple hello-reply exchange as is done inthe art. Further, efficient data routing in an ad hoc network requiresthat a certain level of confidence is established about the persistencein quality of a communication link before adopting that link in routing.

The present invention provides methods and systems for reliable neighbornode discovery.

In one aspect, embodiments of the present invention provide schemes thatencompass a variety of factors, as described above, in the determinationof link quality.

In another aspect, embodiments of the present invention provide measuresto analyze the persistence of a communication link before making adecision about the reliability of that link. In embodiments, basicand/or complex statistical and/or probabilistic analysis may be used.

In a further aspect, embodiments of the present invention providemethods and systems for neighbor node discovery that adapt to networkand/or node operating conditions and that dynamically maintain aneighbor node set at a given node according to these conditions.

Methods and Systems for Reliable Neighbor Node Discovery

Methods and systems for reliable neighbor node discovery will now beprovided. In the description below, various parameters for measuringlink quality, which may be employed in embodiments of the presentinvention, will be described. Equivalent parameters and/or parametersthat may be used for the equivalent purpose of evaluating link qualityalso exist. Accordingly, it should be understood that methods andsystems according to the present invention should not be limited tothose using the parameters described herein, and that schemes usingequivalent and/or other parameters are also within the scope of thepresent invention.

Further, in the course of the description below, various methods andsystems for generating hello/reply message statistics and for analyzingsaid statistics are provided. The present invention is not limited tothe methods and systems provided herein. As equivalent ones exist, theyare also within the scope of the present invention. This similarlyapplies to hello/reply message data, hello/reply message statistics,statistical decision parameters, hello/reply message characteristics,and network conditions as described below.

FIG. 3 is a process flowchart 300 for reliable neighbor node discoveryin a wireless network having a plurality of nodes. Process flowchart 300begins in step 310, which includes broadcasting a hello message from anode in the network. In an embodiment, the node has several networknodes within transmission range thereof, which may be able tosuccessfully receive packets broadcast by the node. Further, nodessuccessfully receiving the broadcast hello message may reply toacknowledge the reception of the message and to notify the broadcastingnode of their presence.

Accordingly, step 320 includes receiving at the broadcasting node replymessages in response to the broadcast hello message from other nodes inthe network. In an embodiment, reply messages may be broadcast in thenetwork or directly unicast to the broadcasting node. A reply messagereceived at the broadcasting node from another node in the networkindicates that a communication link might exist between the two nodes;however, the quality and utility of that link remains to be established.

Upon receiving reply messages, step 330 includes generating hello/replymessage data at the broadcasting node based on the broadcast hellomessage and the received reply messages. In an embodiment, the generatedhello/reply message data may include any type of data that may be usedto infer link quality information between the broadcasting node and itsneighboring nodes. For example, the generated hello/reply message mayinclude, among other parameters, hello/reply message characteristics,origin addresses of the received reply messages, latencies associatedwith the received reply messages, and/or a variable-length dummy payloadto pad the message to a size commensurate with desired traffic packets.

According to embodiments of the present invention, hello/reply messagecharacteristics may include, among other parameters, hello/reply messagesize, hello/reply message frequency, hello/reply message error rates asa function of packet size and radio transmission rate, and/orequivalents thereof, each of which may be used to estimate link qualityfor data transmission. For example, as described above, link qualityvaries according to message size in that shorter messages are typicallymore likely to be received successfully over a noisy link than longermessages. Accordingly, as hello/reply messages are typically of smallersize than data messages, it is important to take into account messagesize when inferring link quality for data message transmission.

Similarly, hello/reply message error rates as well as latenciesassociated with the received reply messages may be used as indicators oflink quality.

Referring back to FIG. 3, step 340 includes repeating steps 310-330 fora time interval much larger than an average inter-hello message periodto generate cumulative hello/reply data. The average inter-hello messageperiod represents an average time duration between two consecutive hellomessage broadcasts, and may be specified as a function of network and/ornode operating conditions as well as the specific ad hoc networkingapplication. In an embodiment, the time interval of step 340 is ofsufficient duration to encompass several hello/reply exchanges and togenerate a reasonably large sample of hello/reply data, which may beused to accurately analyze link quality. For example, the neighbors of anode carried by a pedestrian might be expected to change over the courseof a second; in that case, the average inter-hello message period wouldbe on the order of a tenth of a second.

Step 350 includes processing the cumulative hello/reply data todetermine a neighbor node set of the broadcasting node. The neighbornode set includes network nodes with which the broadcasting node hasreliable symmetric communication links. In an embodiment, step 350further includes generating hello/reply message statistics based on thecumulative hello/reply data. In an embodiment, the generated hello/replymessage statistics include, among other parameters, average replymessage latencies, reply message arrival probabilities, and/orequivalent measures thereof as a function of the varied parameters, suchas message size, data rate, and transmit power.

In another embodiment, step 350 further includes monitoring networkconditions and generating statistical decision parameters for analyzingthe generated hello/reply message statistics. In an embodiment, thestatistical decision parameters are generated based on, among otherparameters, hello/reply message characteristics (described above),network conditions, and/or node operating conditions.

According to embodiments of the present invention, network conditionsinclude network traffic conditions, network loading conditions, networkconnectivity conditions, and/or network volatility conditions. Differentparameters and/or measures may be used to describe each of the notednetwork conditions as understood by a person skilled in the art. Nodeoperating conditions may include, among other parameters, currentneighbor node set, physical layer characteristics, and/or node receiversensitivity.

As understood by a person skilled in the relevant art(s), each of theabove noted parameters may affect link quality and can be used to inferinformation about link quality for data transmission. For example, anode's current neighbor node set may affect the probability of packetcollision when communicating with the node. On the other hand, a node'sphysical layer may treat broadcast hello messages differently thanunicast data messages (802.11, for example, transmits broadcast packetsat a lower rate and without clear-to-send protection), resulting indifferent message reception rates for broadcast and unicast messages.

According to embodiments of the present invention, statistical decisionparameters may be generated so as to incorporate any number ofparameters that may affect link quality for data transmission. Further,statistical decision parameters as well as the type of analysis used mayvary in complexity according to network and/or node operatingconditions. For example, simple threshold analysis based on a decisionthreshold may be sufficient for network conditions that vary slowly. Onthe other hand, adaptive trend analysis based on more complexstatistical decision parameters may be needed for rapidly changingnetwork conditions.

Accordingly, to meet the typically volatile conditions of wireless adhoc networks, embodiments of the present invention further includeadjusting the hello/reply message characteristics, the statisticaldecision parameters, and/or the analysis type according to networkand/or node operating conditions. This results in adaptive methods andsystems for neighbor node discovery that track changes in network and/ornode conditions, and that dynamically adjust the link quality analysisand input parameters thereof accordingly.

FIG. 4 is a block diagram of a system 400 for reliable neighbor nodediscovery that implements process flowchart 300 of FIG. 3. System 400represents components of a neighbor node discovery module connected to anetwork interface. In an embodiment, system 400 may be part of awireless node in a wireless ad hoc network.

System 400 includes a HELLO transmitter module 402, a REPLY receivermodule 406, a medium term memory 408, a statistical analyzer module 410,a neighbor set module 412, a TCP/IP network stack 404, and a networktraffic monitor 414. The operation of system 400 according to processflowchart 300 will now be described.

HELLO transmitter module 402 generates and forwards a hello message toTCP/IP Network Stack 404. In an embodiment, HELLO transmitter module 402may generate hello messages according to an inter-hello message period.The inter-hello message period may be fixed or variable and may bespecified as a function of network conditions.

Each generated hello message includes information for identifying thewireless node in the network. For example, the hello messages include anetwork address of the wireless node. Further, the hello messages may beof fixed or variable size. In an embodiment, HELLO transmitter 402, uponforwarding a hello message to TCP/IP network stack 404, saves messagecharacteristics of the hello message in medium term memory 408.

TCP/IP network stack 404 connects system 400 to the wireless network.Accordingly, upon receiving the hello message from HELLO transmittermodule 402, TCP/IP network stack 404 disseminates the hello message inthe network. In an embodiment, TCP/IP network stack 404 performs aone-hop broadcast of the generated hello message. This means that thehello message is not forwarded by other nodes in the network that mayreceive it. In another embodiment, TCP/IP network stack 404 may notifyHELLO transmitter module 402 of the precise time when the hello messageis transmitted. HELLO transmitter module 402 may then record thatinformation in medium term memory 408.

If the node using system 400 is within communication range of othernetwork nodes, system 400 may receive reply messages from other nodes inthe network. This is done by TCP/IP network stack 404 receiving replymessages and forwarding them to REPLY receiver module 406. REPLYreceiver module 406 extracts information from the received replymessages, and forwards the extracted information to medium term memory408 to be saved. In an embodiment, the extracted information includesmessage characteristics of reply messages as described above. In anotherembodiment, REPLY receiver 406 may compute latencies associated withcommunication links to neighbor nodes by examining receipt timestampsincluded in the received reply messages.

Network traffic monitor 414 monitors traffic though TCP/IP network stack404, and may generate measures of network conditions based on themonitored traffic. In an embodiment, network traffic monitor 414 infersnetwork loading conditions by monitoring traffic through TCP/IP networkstack 404. In another embodiment, network traffic monitor 414 maygenerate traffic pattern (traffic burstiness, for example) data based onmonitoring TCP/IP network stack 404.

Network traffic monitor 414 may communicate the generated data and/orinformation to HELLO transmitter 402, which may examine and save thedata in medium term memory 408. In an embodiment, HELLO transmitter 402may adjust certain characteristics of hello messages based on datareceived from network traffic monitor 414 such as message length, datarate, and transmission rate.

Following several inter-hello message periods, medium term memory 408contains a sufficient amount of hello/reply data to generate meaningfulstatistics for describing link quality between the wireless node andneighbor nodes thereof. In an embodiment, statistical analyzer 410 usesdata saved in medium term memory 408 to generate hello/reply statisticsthat may be used to analyze link quality. In an embodiment, thehello/reply statistics include average reply message latencies, replymessage arrival probabilities, and/or equivalent measures thereof as afunction of the varied parameters, such as message size, data rate, andtransmit power.

Further, statistical analyzer 410 generates statistical decisionparameters for analyzing the generated hello/reply statistics. In anembodiment, statistical decision parameters may be generated so as toincorporate any number of parameters that may affect link quality fordata transmission. In another embodiment, statistical decisionparameters may vary according to the type and complexity of analysisused by analyzer 410. For example, in a wireless ad hoc network havingslowly changing conditions, a simple threshold analysis may besufficient to analyze link quality. Accordingly, generating statisticaldecision parameters, in this case, involves applying a threshold to acount of successful exchanges having the desired characteristics(length, data rate, etc.) to determine whether a link can be classifiedas reliable or not. Generally, more sophisticated statistical analysisis required and may include, but is not limited to, maximum likelihoodanalysis, maximum a priori analysis, fuzzy logic analysis, and hiddenMarkov model analysis.

Statistical analyzer 410 analyzes the reliability of neighborcommunication links based on the generated hello/reply messagestatistics and using the generated statistical decision parameters. Asdiscussed above in the description of process flowchart 300, severalfactors, including network conditions and node operating conditions, maybe incorporated in this statistical analysis. Subsequently, statisticalanalyzer 410 determines the set of neighbor nodes with which reliablesymmetric communication links are present, and stores this set inneighbor set module 412. Neighbor set module 412 includes a means forexposing the neighbor node set to users via visual or audible indicatorsand/or application processes via memory and/or or file-based mechanisms.

FIG. 5 is a block diagram of an example wireless device 500 having aneighbor node discovery module according to the present invention.Wireless device 500 includes an ad hoc networking module 502, avoice-over-ip (VOIP) module 506, a sensor module 508, and a displaymodule 504.

Ad hoc networking module 502 includes a neighbor discovery module 514,which represents a reliable neighbor node discovery module as describedabove with respect to FIG. 4. The neighbor node discovery moduleadaptively generates and maintains a neighbor node set of wirelessdevice 500. Ad hoc networking module 502 may also include a data routingmodule (illustrated using the Ad Hoc Route Determination module in FIG.5) that determines routing paths from wireless device 500 to other nodesin the network. In an embodiment, the data routing module uses theneighbor node set generated by neighbor discovery module 514 in concertwith neighbor node sets from other nodes to determine the routing pathseither proactively or reactively.

VOIP module 506 and sensor module 508 represent data generation and/orreproduction modules. For example, VOIP module 506 includes an audiorecording device for generating data for transmission and an audioplayback device for reproducing data received from the network.Similarly, sensor module 508 includes several data generation componentssuch as the data capture components and several data reproductioncomponents such as the data display components.

Display module 504 displays network connectivity information of thewireless device, which can be used by a user of the device and/or thenetwork. Display module 504 includes one or more light emitting diodes(LEDs). In an embodiment, display module 504 includes a first LED 510for indicating whether the neighbor node set is empty or not. In otherwords, the first LED 510 indicates whether the wireless device has anynetwork nodes within reliable communication range. In anotherembodiment, display module 504 includes a second LED 512 to indicatewhether a command node, which may include a central control entity ofthe network, is included in the neighbor node set of the wirelessdevice. The second LED 512 may be useful in ad hoc networkingapplications that use command nodes, such as team communicationapplications, or data exfiltration/storage nodes, such as wirelesssensor networking applications. Display module 504 is controlled byneighborhood module 514 based on the generated neighbor node set.

Display module 504 represents a novel feature according to the presentinvention. Indeed, display module 504 significantly simplifies theprocess of deploying an ad hoc network when the goal is to have a fullyconnected network with no partitions. In an embodiment, display module504 can be used to determine where to place relay nodes in the networkin order to maintain full connectivity in the network. Placement basedon timely indication of reliable neighbors can be done conveniently andaccurately by users with minimal training and without the need forsophisticated test equipment, such as radio frequency spectrumanalyzers.

CONCLUSION

While various embodiments of the present invention have been describedabove, it should be understood that they have been presented by way ofexample only, and not limitation. It will be apparent to persons skilledin the relevant art that various changes in form and detail can be madetherein without departing from the spirit and scope of the invention.Thus, the breadth and scope of the present invention should not belimited by any of the above-described exemplary embodiments, but shouldbe defined only in accordance with the following claims and theirequivalents.

1. A wireless device for use in a wireless ad hoc network, comprising: awireless network interface that connects said wireless device to saidwireless ad hoc network; a neighbor node discovery module that generatesa neighbor node set of said wireless device; and a display module thatdisplays network connectivity information of said wireless device;wherein said neighbor node discovery module comprises: a transmitterconfigured to generate and forward a plurality of HELLO messages to saidwireless network interface according to a specified messaging rate,wherein said plurality of HELLO messages are characterized by one ormore of variable HELLO message packet sizes and variable transmissiondata rates; a receiver configured to receive at least one REPLY messagefrom said wireless network interface in response to each of saidplurality of HELLO messages; a memory configured to store cumulativeHELLO/REPLY message data generated based on said plurality of HELLOmessages and REPLY messages received in response thereto; and astatistical analyzer module configured to analyze said cumulativeHELLO/REPLY message data stored in said memory to generate said neighbornode set of said wireless device.
 2. The wireless device of claim 1,wherein said neighbor node discovery module further comprises: a networktraffic monitor configured to monitor traffic through said wirelessnetwork interface and to generate information regarding networkconditions based on the monitored traffic.
 3. The wireless device ofclaim 2, wherein said network traffic monitor communicates the generatedinformation regarding network conditions to said transmitter, whereinsaid transmitter adjusts characteristics of said HELLO message based onsaid generated information.
 4. The wireless device of claim 1, whereinsaid transmitter is configured to generate said HELLO message accordingto an inter-hello message period.
 5. The wireless device of claim 4,wherein said inter-hello message period is set according to networkconditions.
 6. The wireless device of claim 1, wherein said transmitteris configured, upon forwarding said HELLO message to said wirelessnetwork interface, to store information regarding said HELLO message insaid memory.
 7. The wireless device of claim 1, wherein said receiver isconfigured to extract information from said REPLY message and to storesaid extracted information in said memory.
 8. The wireless device ofclaim 1, wherein said statistical analyzer module is configured toanalyze said information stored in said memory to generate HELLO/REPLYstatistics.
 9. The wireless device of claim 1, wherein said neighbornode discovery module controls said display module based on thegenerated neighbor node set.
 10. The wireless device of claim 1, whereinthe display module comprises one or more light emitting diodes (LEDs),wherein one of said LEDs is on when said neighbor node set is non-emptyand is off when said neighbor node set is empty.
 11. The wireless deviceof claim 10, wherein another one of said LEDs is on when said neighbornode set includes a command node of said wireless ad hoc network and isoff when said neighbor node set does not include said command node.